1. Field of the Invention
The present invention relates to a shutter device of a camera including a lens-fitted film unit and so forth.
2. Description of the Related Art
As a lens-fitted film unit in which a new film cartridge is loaded at the time of manufacture thereof, there are "Quick Snap Super Slim (trade name)" and so forth. they are manufactured and sold by the assignee of the present application. In such a lens-fitted film unit, troublesome operation of film loading and film rewinding is unnecessary.
The lens-fitted film unit has a film roll chamber and a cartridge chamber. In the film roll chamber, a film is contained in a roll state. In the cartridge chamber, a cartridge taking up the exposed film is contained. Between the film roll chamber and the cartridge chamber, a light shielding member is provided. An exposure unit comprising a shutter device and a film stopping device is attached to the light shielding member.
The shutter device is constituted of a lens holder, a shutter blade and a base member. A taking lens is attached to the lens holder. The shutter blade is rotatable between a close position where a photographic optical path is shut off and an open position where the optical path is not shut off. The base member supports the shutter blade between itself and the lens holder. The shutter blade is integrally formed with a kicked member. The kicked member protrudes from an upper gap formed between the lens holder and the base member. The kicked member is kicked by a shutter driving lever in association with a shutter release operation so that the shutter blade is rotated.
In order to decrease the cost of the lens-fitted film unit, a shutter button thereof is formed by cutting an upper portion of a front cover. Thus, fine sand, dust and the like sometimes enter its unit body from the cut portion of the front cover. Although the lens holder entirely covers a front side of the base member, the fine sand or the like enters a space formed between the base member and the lens holder through the upper gap from which the kicked member protrudes. Accordingly, there arises a problem in that a rotational movement of the shutter blade becomes bad before the lens-fitted film unit is used up. Further, there arises another problem in that the sand or the like enters the light shielding member from a shutter opening and injures a photographic film.